02 TDI Jetta grille block

[deejaaa]

i am hitting between 55-59 inst mpg(ultragauge) compared to 49-53, no drafting, flat concrete interstate(conditions were the same, as best as i could get them). stop n go, ac on, rain, temp climbed to 210 but fell to 197, where it stays while cruising. fill up yesterday but forgot to clear trip odo so will have to wait till next tank bc i can get over 900 mpt.
using silicone, placed 3 larger than opening pieces of coroplast together, held down with cans on flat surface.
removed grille.

marked areas to remove, using grinder with cut off wheel, removed/beveled sections to fit.

added salvaged wiper strands into slots and added a rear support to prevent deformation.


added 2 more pieces to bring it close to flush, adding spacer to form curve.



silicone/tape was used to attach/seal/hold edges.

bent plate , relocated to center bumper, held on with silicone after this pic.

needs some fine tuning around edges of last layer.
so far so good.
no finished pic but will get one later to show contour of leading edge.

[Daox]

A lot of the TDI guys cut out the upper corner of their grill blocks for the intake. But if this is working for you, great.

[deejaaa]

i thought about that but the whole area in front/below the rad is open as well as the lower opening. so far it's working but i will see. i have an open(ed) mind.

[Daox]

Did you monitor intake temps before and after, just out of curiosity?

[deejaaa]

nothing wrote down but ultragauge read 70's in the morn, low 100's evenings. i will check on the way home today.

[NachtRitter]

Cool! errr... Hot! I like the license plate over the driver's side grill.

Mine for reference (a little dirty from a trip):



Used foam between the slats to do the block... yours looks better though.

[deejaaa]

thank you. i moved the plate to the bumper after that pic, attached with silicone after it was bent to shape. i have the mounting hardware if you want it. stainless and copper.
this is in the "68 vehicle mods for better fuel economy ...'
'Grill blocks come in many forms, though most often they are made to be flush with the outside of the bumper for greatest benefit. Simply inserting a piece of cardboard in front of the radiator does not provide the same aerodynamic benefit.'
65+ Vehicle modifications for better fuel economy - EcoModder.com

[deejaaa]

Originally Posted by Daox

Did you monitor intake temps before and after, just out of curiosity?

IAT on the way home, between 4 and 5 pm, was 91* so there is no impact on that.

EDIT:
between 6:30-7:30 this morn IAT was 73*.

[deejaaa]

ended up blocking the 2 lower openings a few weeks ago and today put in the HID's and added some covers for the openings between the skid plate/front dam to smooth the flow some. will see tomorror on the way to work if it makes a difference. plastic came from a mud flap that i picked up off the side of the road.
here's the pieces installed on the bumper cover:


best shots i could get:

need to get it on ramps, drill a hole and bolt both of the corners to the skid plate so they won't be hanging so low.

openings closed:

i reinstalled the rear flat deck fin, boxed the rear somewhat.
this is the best i could do at the moment but i will try to make the transformation a little better when i get the chance:

[NachtRitter]

Thanks for the pics! I did something similar to what you did with the bumper-to-skidplate transition, though with a bit more coverage... will have to get some pics of that the next time I take off the front bumper. And I've been trying to figure out the rear too... had ideas similar to what you did, but seeing how you did it is awesome! Think that helped FE?

Edit: Oh look, I'd already taken a pic:


(Hope you don't mind me adding pics of my mods in your Jetta mods thread)